1. Field of the Invention
The invention relates to an iris recognition camera for an iris recognition system and a method of operation for an iris recognition camera.
2. Background of the Related Art
In recent years, systems for validating personal identification have been widely used for security purposes. Such systems verify personal identification and allow a verified individual to enter into a restricted area or access to restricted information. Such systems, contact or non-contact type card systems, fingerprint recognition systems, and iris recognition systems are well known.
More particularly, iris recognition systems have been used more and more in recent years. With iris recognition systems, there is no need to possess personal information, storing means, or of contacting any portion of the user's body.
FIG. 1 shows a schematic diagram of a related art iris recognition system.
As shown in FIG. 1, when a user approaches the iris recognition system 10, a distance-measuring device 9, such as a sensor, measures a distance to the user. Then, the measured distance value is transmitted to a controller 5 through a driver 7 and the controller 5 determines if the measured distance value is within an operation range. When it is determined that the distance should be corrected, the user is notified. When it is determined that the distance is within the operation range, the controller 5 transmits a control signal to the driver 7 so that the system can prepare to scan an iris image.
In addition, the driver 7 transmits an active signal to a display 8 to let the user know operation of the system is about to begin. Then, when the user aligns his/her eye(s) with an optical axis of a camera 3 through an optical window 1, a cold mirror 2 allows an infrared ray to be transmitted from the user's eye to the camera while interrupting a visible ray. At this point, the system 10 displays a location of the user's iris so that the user can determine whether his/her eye(s) is located on the optical axis.
In addition, the controller 5 performs a zoom in/out and focusing control by calculating zoom and focus values based on the distance value transmitted from the distance-measuring sensor 9. Afterwards, the controller 5 adjusts an intensity of a lighting device 6 through the driver 7 in accordance with the measured distance value, and takes a photograph of the iris using the camera 3. The photographed iris image is signal-processed in response to an iris image analysis in a frame graver 4, and the controller 5 performs the recognition of the iris using the signal-processed iris image information.
In the above-described related art iris recognition system, the camera 3 performs a zoom in/out function, as well as a focusing function. That is, the iris recognition camera 3 is provided with a zoom lens system for performing the zoom in/out function and a focus lens system for performing the focusing operation. The zoom lens system and the focus lens system are independently operated and adjusted in their positions. Further, the zoom lens system and the focus lens system are reciprocally controlled by respective driving parts.
However, because of the independent operations of the respective zoom lens system and the focus lens system by the respective driving parts, the structure is complicated, which increases manufacturing costs.
In addition, since the zoom and focus functions are independently realized in sequence, a lot of time is required for the operation of the camera.
Meanwhile, other conventional art iris recognition systems have been designed such that zoom and focus operations are not performed in the camera, but rather the camera lets the user know a direction and distance the user has to move. However, in this case, since the user has to move upward and downward, rightward and leftward, and frontward and rearward by himself/herself to align his/her eye(s) with the optical axis, it is inconvenient for the user.